Viral Hepatitis Flashcards
what is viral hepatitis?
Inflammation of the liver due to a virus
what is the inflammatory mechanism of viral hepatitis?
infects cells in liver causing them to express MHC1 molecules, recognised by CD8+ cells and initiate cytotoxic killing and apoptosis?
what are the general symptoms of viral hepatitis?
- Fever, malaise, nausea
- Hepatomegaly
- Pain
- ↑ blood transaminase
- ↑ atypical lymphocytosis
- Jaundice
what is the definition of acute viral hepatitis?
<6 months
what is the definition of chronic viral hepatitis?
> 6 months
what are the types of viral hepatitis?
A,B,C,D,E
what is the structure of hepatitis A?
Picornvirus – not enveloped, contains single stranded RNA in protein shell (Epstein barr?)
what is the route of spread of hepatitis A?
faecal oral route
what is the incubation period of hepatitis A?
2-4 weeks
what are the clinical features of hepatitis A
o Always acute (no carrier state)
o Common in travellers
o Flu like symptoms
o Jaundice or hepatosplenomegaly
what is the diagnostic serology of hepatitis A?
HAV IgM = Active
HAV IgG = recovery or vaccination
what is the management of hepatitis A?
Supportive
Treatment
What is the structure of hepatitis E?
single stranded, non enveloped RNA, cosahedral virus (hepevirus, cytomegaly virus)
how is hepatitis E spread?
faecal oral
what is the incubation period of hepatitis E?
o Always acute
o Similar to Hep A but greater mortality risk in pregnancy
what is the diagnostic serology of hepatitis E?
o HEV IgM = Active
o HEV IgG = recovery
what is the management of hepatitis E?
Supportive
No vaccine
what is the structure of hepatitis C?
RNA flavivirus
how is hepatitis C spread?
Blood spread – childbirth, sex, IV drug users
what is the intubation period of hepatitis C?
6-9 weeks
what are the two clinical presentations of hep C?
acute and chronic
what are the clinical features of acute hepatitis C?
Systemic – fatigue, nausea, joint pain, anorexia
↑ serum aminotransferase
Jaundice
what are the clinical features of chronic hepatitis C?
Rheumatological problems – athralgia, arthritis
Eye problems – sjogrens
Cirrhosis
Hepatocellular cancer
Cryoglobulinaemia: typically type II
Porphyria cutanea tarda
Membranoproliferative glomerulonephritis
what is the gold standard diagnostic test for hepatitis C?
HCV RNA (with PCR) • Levels decrease = recovery
what are the diagnostic tests for hepatitis C?
Enzyme immunoassay – HCV IgG (doesn’t indicate active or protective disease)
Recombinant immunoblot - ↑↓
HCV RNA (with PCR)
what is the management of acute hepatitis C?
supportive
what is the management of chronic hepatitis C?
• Combination of protease inhibitors
o Daclatasvir + sofobuvir
o Sofosbuvir + simeprevir
• Interferon based treatments no longer recommended
• Liver transplant – virus recurs afterwards
what is the structure of hepatitis B?
hepadnaviral
o Double stranded DNA
o Outer lipid envelope and an icosahedral nucleocapsid core
what is the other name for hepatitis B?
yellow fevelr
how is hepatitis B spread?
o Blood (body fluid?) spread – sex, vertically (more likely to be chronic) Carriers exist
what is the intubation period of hepatitis B?
6-20 weeks
what are the serology features used in testing of hepatitis B?
o PCR can be used to look for makers
o HBV surface antigen – lives on surface = HBsAg
o Core antigen – lives in core of virus = HBcAg
o E Antigen – biproduct of replication = HBc = marker of active infection
what are the clinical features of hepatitis B?
o Systemic – fever
o Jaundice
what are the complications of hepatitis B?
o Chronic hepatitis o Fulminant liver failure o Hepatocellular carcinoma o Glomerulonephritis o Polyarteritis nodosa o Cryoglobulinaemia
what are the infective stages of hepatitis B?
active, initial immune response windows phase, acute end or chronic state
what is the serology of the active phase of hepatitis B?
HBsAg is present and showing posistive – viral DNA + E antigen also
o Antibodies are produced from IgM against HBcAg
what are the serological features of the windows phase of hepatitis B?
neither surface antigen or IgG are detected as levels are so low – can detect core IgM antibodies
what is the serology in successful end of hepatitis B infection?
IgM
what are the serology features if an immune response is unsuccessful in hepatitis B?
Surface antugens detected, no IgG
Also presence of HBV DNA and antigen presence
what is the serology in healthy chronic state hepatitis B?
presence of surface antigen and core antibody but no E antigen
what is the serology of infective chronic state hepatitis B?
HBsAg, JBcAg, e antigen (all present)
what are the prevention methods for hepatitis B?
minimse exposure: safe blood, safe sex, needle exchange, prevention of needlesticks, screening of pregnant women
Vaccination
what is the management of hepatitis B?
o Pegylated interferon – alpha used
o Other anti-virals – tenofovir and entecavir
o Post exposure prophylaxis - vaccine, plus HBIG
what is the virology of hepatitis D?
single stranded RNA virus
what needs to be present for hepatitis D infection?
o Requires Hep B surface antigen to complete replication and transmission cycle
Co infection or super infection
what are the clinical features of hepatitis D?
o Link with superinfection
o High risk of fulminant hepatitis (pregnancy), chronic hepatitis, cirrhosis
what is the diagnostic test for hepatitis D?
reverse PCR reaction of hepatitis D RNA
what is the management of hepatitis D?
interferon
